An ultrasound scanning device is a convenient and noninvasive choice for cardiac monitoring, and is extensively applied in ICUs (Intensive Care Units), operating rooms, and occasions such as when moving a patient, due to its capacity to detect the movement information and structure of tissues and organs. The ultrasound scanning device can be used to continuously monitor real-time parameters of the patient's heart movements for a long period of time. The real-time parameters are hemodynamic parameters such as ejection fraction, ventricular volume, and blood flow rate. When in use the same cardiac section is scanned repeatedly, such that stable and consistent diagnostic parameters from the same cardiac section are acquired.
When the patient cannot breath on his own, such as when completely unconscious or under general anesthesia, a ventilator is required to perform respiratory ventilation on the patient. Respiratory assistance is one of the key means to rescue emergency or critical patients. Therefore, the ventilator is indispensable in clinical care. The breathing machine is more and more widely applied in fields of first aid, anesthesia, intensive care, and respiratory therapy. The ventilator can replace, control or change the normal physiological respiration of a person, increasing pulmonary ventilation volume, improving respiratory function, alleviating respiration consumption, and saving a cardiac reserve capability.
However, in practical clinical applications, because an increase in lung capacity is caused by mechanical ventilation, the lung tissue moves toward the heart and causes the position of the heart to change. The scanning region of the heart by the conventional ultrasound scanning device is constant. Once the position of the heart is changed, it is equivalent to that the ultrasound scanning device scanning different regions at different times and even the region outside the heart is scanned. This interferes with the stability and accuracy of images captured by the ultrasound scanning device.
FIGS. 1 and 2 show sectional views along a ventricular short axis. The white line segments in FIGS. 1 and 2 indicate the same reference position, and it is apparent the heart moves from side to side due to an air feed of the ventilator causes the section scanned by the scanning line to be changed accordingly. Therefore, the data acquired by the scanning line is not based upon the same section, such that the ultrasound scanning result loses its meaning. Therefore, in existing clinical conditions, the scanning of the ultrasound scanning device is generally controlled by the doctor via perusal, and the stability and the accuracy of the scanning result is inadequate.